<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>案例3</title>
		<style type="text/css">
			#div1{
				width: 200px;
				height: 200px;
				margin: 20px auto;
			}
			#btn1{
				width: 50px;
				height: 50px;
			}
		</style>
	</head>
	<body>
		点击按钮实现累加
		<div id="div1">
			
			<input type="button" name="" id="btn1" value="0" />
		</div>
		
	</body>
</html>
<script src="../js/jquery-3.5.1.min.js" type="text/javascript" charset="utf-8"></script>
<script src="./js/test3.js" type="text/javascript" charset="utf-8"></script>